A Czochralski crystal growth technique is frequently used to grow single crystals. In this technique, a melt is formed by heating a material in a crucible. A single crystal is then grown by withdrawing a rotating seed crystal that is in contact with the melt. As the seed crystal is withdrawn or pulled from the crucible, the melt solidifies on the seed. A pulling head arrangement, which is part of a crystal growth furnace apparatus, is typically used to pull the single crystal.
An oxyorthosilicate material may be used to form a single crystal. For example, single crystals fabricated from an oxyorthosilicate material may be used in detectors for positron emission tomography (PET) medical scanners utilized in molecular imaging. An oxyorthosilicate crystal is typically grown in the form of a long cylindrical boule. The boule is grown until a target weight is achieved to form a full size boule. A relatively large capacity load cell or scale is used to weigh a full size boule. On the other hand, the boule is relatively light during initial stages of formation of the boule.
It is important to be able to determine the weight of the boule during initial stages of formation of the boule. However, the relatively large capacity scales that are used to weigh a full-size boule do not have sufficient resolution to be able to accurately determine the weight of a relatively light boule.